php字符串截取函数用法

".$str."
"; //按各种方式进行截取 $str1 = substr($str,5); echo "从第5个字符开始取至最后：".$str1."
"; $str2 = substr($str,9,4); echo "从第9个字符开始取4个字符：".$str2."
"; $str3 = substr($str,-5); echo "取倒数5个字符：".$str3."
"; $str4 = substr($str,-8,4); echo "从倒数第8个字符开始向后取4个字符：".$str4."
"; $str5 = substr($str,-8,-2); echo "从倒数第8个字符开始取到倒数第2个字符为止：".$str5."
"; ?>

 $length) { for($i=0; $i < $length; $i++) if (ord($str_cut[$i]) > 128) $i++; $str_cut = substr($str_cut,0,$i).".."; } return $str_cut; } ?>